took daily two drams of solid opium, but not without injury to her fine mental faculties. I may mention another instance, and one more extraordinary, which came to my knowledge at Constantinople, of a Turk who took daily, and for fifteen years, two drams of solid opium, with half that quantity of corrosive sublimate. My informant knew the man well, he was a porter at the arsenal (of which my friend was an official), and though in shattered health, was capable of his easy duties. I obtained a specimen of what was used as corrosive sublimate, and, testing it, found it to be this compound, of ordinary purity. The main motive for its use, he said was, that it improved-increased, the effects of the opium. This instance, according to the apothecaries in Pera, is not a solitary one of its kind; their experience having taught them that the opium-eater has recourse to it when the narcotic has ceased to have its original effect.

The tolerance of certain substances, in connection with their elimination, has not, I am disposed to think, had all the attention which it deserves. Why is it that individuals living under the same circumstances, using the same kind of diet and the same drinks, are some of them subject to gout, whilst others are free from it? Is it not because the latter possess in their organisation a greater power of eliminating the causa mali-lithic acid? Why is it that nitrate of silver long used, in some persons (the very few) becomes -that is the metal-lodged in the cutis vera, occasioning there its peculiar discolouring effect, whilst in the majority, after long use, no effect of the kind is witnessed? Is not the rationale of the difference the same?

We have had it confirmed that the water of Whitbeck is, in the solitary instance of the duck, injurious; ultimately it would appear to be fatal. This may be owing, it may be conjectured, to the duck seeking its food so much more in water, and to a delicacy, an idiosyncrasy rendering it peculiarly susceptible of the effect of arsenic; a peculiarity itself which may be connected with a feeble eliminating power, especially of the kidneys, its urine, like that of birds in general, approaching to a solid.

A somewhat similar instance of great susceptibility of the effects of arsenic occurs, I believe, in the charr, one of the NEW SERIES.-VOL. XVIII. NO. I.-JULY 1863.

G

most delicate, the most sensitive of noxious influences of all the Salmonidæ. It is an established fact, that in the two or three instances in the Lake District, that mines have been opened in the vicinity of lakes, their drainage entering the lakes, the charr has either entirely disappeared, as at Ulswater, or has become very scarce, as at Coniston-water, the trout, a hardier fish, remaining. I have examined the water flowing from the Coniston copper mines into the lake of the same name, and have detected in it distinct traces of arsenic; and I have obtained a like result from the examination of the water flowing into Ulswater, which receives the drainage of an adjoining lead mine.

Recently, much alarm has been felt from apprehension of arsenic-poisoning, owing to the great use made of some of its compounds, especially of Scheele's green-the cuprioarseniate-in colouring paper and articles of dress. Probably the apprehension is an exaggerated one; but yet there seems some foundation for it, especially in the case of women employed in making artificial flowers, and in that of ladies wearing those flowers in ball-dresses, coloured by the arsenic compound. If there were only a risk of injury, and that there certainly is in these instances, of a poisonous effect, ought it not to act powerfully as a prohibition to the further use of articles so coloured? Even the most insensate votaries of fashion who may defend crinoline, asserting that, with caution, they are safe from combustion, will hardly venture to defend the use of a poisoned dress, from the slow effects of which, undermining health and spoiling beauty, no ordinary precautions can be effectual.

When we reflect on the abundance of arsenical pyrites in most of our mining districts, and the numerous springs issuing from mineral strata, the water of which is used by the inhabitants, it may be asked how is it that arsenicated water is not of common occurrence, and its poisonous qualities well established? The answer to this, I apprehend, is not difficult, resting on two facts-one, the slight solubility of the oxide of the metal in cold water; the other, its harmlessness in very minute quantities. As to the first, so slowly is it soluble at ordinary temperatures, that we learn, on good authority, it may be digested for many days with

100,000 times its weight of water, and yet not be entirely dissolved. This, its slowness of solution, is probably owing to its comparatively high specific gravity, in consequence of which the oxide falls to the bottom, and to the strong coherence of its particles, resisting its disintegration. Whatever the explanation may be, the property is a fortunate one for animal life; for were it readily soluble, were it more than very slightly soluble, how direful might have been the results! May we not view it as one of the many happy adaptations which are so common in the economy of Nature, and an instance of the limitation of the noxious, or its neutralization, or even more, of its transition into positive good? this last, on the supposition that arsenic used in a very minute quantity may really be beneficial.

Illustrations of the Significance of certain Ancient British Skull Forms. By DANIEL WILSON, LL.D., Professor of History and English Literature, University College, Toronto.

During a recent visit to Washington, I availed myself of the facilities afforded me by Professor Henry, the learned secretary of the Smithsonian Institution, to examine with minute care the ethnological collections preserved there, including those formed by the United States Exploring Expedition; and especially a highly interesting collection of human crania. The latter includes those of Esquimaux and Tchuktchi, a number of compressed and greatly distorted Chinook and other Flathead skulls, as well as examples of those of other Indian tribes, both of North and South America; and of Fiji, Kanaka, and other Pacific islanders. On my return I spent a short time in Philadelphia, chiefly for the purpose of renewed study of the valuable materials of the Mortonian collection; and while there enjoyed the opportunity of examining, in company with Dr Aitken Meigs, a series of one hundred and twenty-five Esquimaux crania obtained by Dr Hayes in his Arctic journey of 1854.

The materials for craniological investigation which such collections supply can scarcely be surpassed in some of their

departments, and invite to very diverse researches by the illustrations they are calculated to afford. It chanced, however, that my attention had been recently recalled to an old subject of speculation, relative to the possible modification of the forms of ancient British crania by some of the very causes which so materially alter those of many American tribes; and this accordingly influenced me in part, in the notes I made of the collections both at Washington and Philadelphia, and will now give direction to some remarks bearing on the same inquiry.

Among the most prized crania in the collection of the Academy of Natural Sciences at Philadelphia is the celebrated Scioto Mound skull. But though on a former visit I made the ancient mound crania an object of special study, this most remarkable example of the series was not then included among them; and I now examined the original for the first time. The result of this examination was to satisfy me that the remarkable form and proportions of that skull are much more due to artificial influences than I had been led to suppose from the views published in the "Smithsonian Contributions to Knowledge."* The vertical view, especially, is very inaccurate. In the original it presents the peculiar characteristics of what I have before designated as the truncated form; passing abruptly from a broad flattened occiput to its extreme parietal breadth, and then tapering with slight lateral swell, until it reaches its least breadth immediately behind the external angular process of the frontal bone. The occiput has been subjected to the flattening process to a much greater extent than is apparent from the drawings; but at the same time it is accompanied by no corresponding affection of the frontal bone, such as inevitably results from the procedure of the Chinooks and other Flathead tribes; among whom the desired cranial deformation is effected by bandages crossing the forehead, and consequently modifying the frontal as much as the parietal and occipital bones. On this account, great as is the amount of flattening in this remarkable skull, it is probably due solely to the undesigned pressure of the cradle-board acting

→ Ancient Monuments of the Mississippi Valley, pl xlvii. and xlviii.

on a head of remarkably brachycephalic proportions and great natural posterior breadth. The forehead is fully arched, the glabella prominent, and the whole character of the frontal bone is essentially different from the Indian type. The sutures are very much ossified, and even to some extent obliterated. So early as 1857, when discussing Dr Morton's theory of one uniform cranial type pervading the whole ancient and modern tribes of North and South America, with the single exception of the Esquimaux, I remarked, "I think it extremely probable that further investigation will tend to the conclusion that the vertical or flattened occiput, instead of being a typical characteristic, pertains entirely to the class of artificial modifications of the natural cranium familiar to the American ethnologist alike in the disclosures of ancient graves, and in the customs of widely separated living tribes."*

This idea received further confirmation from noticing the almost invariable accompaniment of such traces of artificial modification, with more or less inequality in the two sides of the head. In the extremely transformed skulls of the Flathead Indians, and of the Natchez, Peruvians, and other ancient nations by whom the same barbarous practice was encouraged, the extent of this deformity is frequently such as to excite surprise that it could have proved compatible with the healthful exercise of any vital functions. But the aspect in which it is now purposed to review the subject of artificial modifications of the human cranium, in relation to ancient British skull forms, was suggested, in the same paper above referred to, when pointing out the mistaken idea adopted by Dr Morton, that such unsymmetrical conformation, or irregularity of form, is peculiar to American crania. The latter remark, I then observed, is too wide a generalisation. I have repeatedly noted the like unsymmetrical characteristics in the brachycephalic crania of Scottish barrows, and it has occurred to my mind, on more than one occasion, whether such may not furnish an indication of some partial compression, dependent, it may be,

* Edinburgh Philosophical Journal, n.s., vol. vii. p. 24. Canadian Journal, vol. ii. p. 406.

+ Crania Americana, p. 115. Types of Mankind, p. 444.